1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright 2019 Google LLC
4  */
5 
6 #ifndef __LINUX_BLK_CRYPTO_INTERNAL_H
7 #define __LINUX_BLK_CRYPTO_INTERNAL_H
8 
9 #include <linux/bio.h>
10 #include <linux/blk-mq.h>
11 
12 /* Represents a crypto mode supported by blk-crypto  */
13 struct blk_crypto_mode {
14 	const char *name; /* name of this mode, shown in sysfs */
15 	const char *cipher_str; /* crypto API name (for fallback case) */
16 	unsigned int keysize; /* key size in bytes */
17 	unsigned int ivsize; /* iv size in bytes */
18 };
19 
20 extern const struct blk_crypto_mode blk_crypto_modes[];
21 
22 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
23 
24 int blk_crypto_sysfs_register(struct request_queue *q);
25 
26 void blk_crypto_sysfs_unregister(struct request_queue *q);
27 
28 void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
29 			     unsigned int inc);
30 
31 bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio);
32 
33 bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
34 			     struct bio_crypt_ctx *bc2);
35 
bio_crypt_ctx_back_mergeable(struct request * req,struct bio * bio)36 static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
37 						struct bio *bio)
38 {
39 	return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
40 				       bio->bi_crypt_context);
41 }
42 
bio_crypt_ctx_front_mergeable(struct request * req,struct bio * bio)43 static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
44 						 struct bio *bio)
45 {
46 	return bio_crypt_ctx_mergeable(bio->bi_crypt_context,
47 				       bio->bi_iter.bi_size, req->crypt_ctx);
48 }
49 
bio_crypt_ctx_merge_rq(struct request * req,struct request * next)50 static inline bool bio_crypt_ctx_merge_rq(struct request *req,
51 					  struct request *next)
52 {
53 	return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
54 				       next->crypt_ctx);
55 }
56 
blk_crypto_rq_set_defaults(struct request * rq)57 static inline void blk_crypto_rq_set_defaults(struct request *rq)
58 {
59 	rq->crypt_ctx = NULL;
60 	rq->crypt_keyslot = NULL;
61 }
62 
blk_crypto_rq_is_encrypted(struct request * rq)63 static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
64 {
65 	return rq->crypt_ctx;
66 }
67 
68 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
69 
blk_crypto_sysfs_register(struct request_queue * q)70 static inline int blk_crypto_sysfs_register(struct request_queue *q)
71 {
72 	return 0;
73 }
74 
blk_crypto_sysfs_unregister(struct request_queue * q)75 static inline void blk_crypto_sysfs_unregister(struct request_queue *q) { }
76 
bio_crypt_rq_ctx_compatible(struct request * rq,struct bio * bio)77 static inline bool bio_crypt_rq_ctx_compatible(struct request *rq,
78 					       struct bio *bio)
79 {
80 	return true;
81 }
82 
bio_crypt_ctx_front_mergeable(struct request * req,struct bio * bio)83 static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
84 						 struct bio *bio)
85 {
86 	return true;
87 }
88 
bio_crypt_ctx_back_mergeable(struct request * req,struct bio * bio)89 static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
90 						struct bio *bio)
91 {
92 	return true;
93 }
94 
bio_crypt_ctx_merge_rq(struct request * req,struct request * next)95 static inline bool bio_crypt_ctx_merge_rq(struct request *req,
96 					  struct request *next)
97 {
98 	return true;
99 }
100 
blk_crypto_rq_set_defaults(struct request * rq)101 static inline void blk_crypto_rq_set_defaults(struct request *rq) { }
102 
blk_crypto_rq_is_encrypted(struct request * rq)103 static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
104 {
105 	return false;
106 }
107 
108 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
109 
110 void __bio_crypt_advance(struct bio *bio, unsigned int bytes);
bio_crypt_advance(struct bio * bio,unsigned int bytes)111 static inline void bio_crypt_advance(struct bio *bio, unsigned int bytes)
112 {
113 	if (bio_has_crypt_ctx(bio))
114 		__bio_crypt_advance(bio, bytes);
115 }
116 
117 void __bio_crypt_free_ctx(struct bio *bio);
bio_crypt_free_ctx(struct bio * bio)118 static inline void bio_crypt_free_ctx(struct bio *bio)
119 {
120 	if (bio_has_crypt_ctx(bio))
121 		__bio_crypt_free_ctx(bio);
122 }
123 
bio_crypt_do_front_merge(struct request * rq,struct bio * bio)124 static inline void bio_crypt_do_front_merge(struct request *rq,
125 					    struct bio *bio)
126 {
127 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
128 	if (bio_has_crypt_ctx(bio))
129 		memcpy(rq->crypt_ctx->bc_dun, bio->bi_crypt_context->bc_dun,
130 		       sizeof(rq->crypt_ctx->bc_dun));
131 #endif
132 }
133 
134 bool __blk_crypto_bio_prep(struct bio **bio_ptr);
blk_crypto_bio_prep(struct bio ** bio_ptr)135 static inline bool blk_crypto_bio_prep(struct bio **bio_ptr)
136 {
137 	if (bio_has_crypt_ctx(*bio_ptr))
138 		return __blk_crypto_bio_prep(bio_ptr);
139 	return true;
140 }
141 
142 blk_status_t __blk_crypto_init_request(struct request *rq);
blk_crypto_init_request(struct request * rq)143 static inline blk_status_t blk_crypto_init_request(struct request *rq)
144 {
145 	if (blk_crypto_rq_is_encrypted(rq))
146 		return __blk_crypto_init_request(rq);
147 	return BLK_STS_OK;
148 }
149 
150 void __blk_crypto_free_request(struct request *rq);
blk_crypto_free_request(struct request * rq)151 static inline void blk_crypto_free_request(struct request *rq)
152 {
153 	if (blk_crypto_rq_is_encrypted(rq))
154 		__blk_crypto_free_request(rq);
155 }
156 
157 int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
158 			     gfp_t gfp_mask);
159 /**
160  * blk_crypto_rq_bio_prep - Prepare a request's crypt_ctx when its first bio
161  *			    is inserted
162  * @rq: The request to prepare
163  * @bio: The first bio being inserted into the request
164  * @gfp_mask: Memory allocation flags
165  *
166  * Return: 0 on success, -ENOMEM if out of memory.  -ENOMEM is only possible if
167  *	   @gfp_mask doesn't include %__GFP_DIRECT_RECLAIM.
168  */
blk_crypto_rq_bio_prep(struct request * rq,struct bio * bio,gfp_t gfp_mask)169 static inline int blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
170 					 gfp_t gfp_mask)
171 {
172 	if (bio_has_crypt_ctx(bio))
173 		return __blk_crypto_rq_bio_prep(rq, bio, gfp_mask);
174 	return 0;
175 }
176 
177 /**
178  * blk_crypto_insert_cloned_request - Prepare a cloned request to be inserted
179  *				      into a request queue.
180  * @rq: the request being queued
181  *
182  * Return: BLK_STS_OK on success, nonzero on error.
183  */
blk_crypto_insert_cloned_request(struct request * rq)184 static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq)
185 {
186 
187 	if (blk_crypto_rq_is_encrypted(rq))
188 		return blk_crypto_init_request(rq);
189 	return BLK_STS_OK;
190 }
191 
192 #ifdef CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK
193 
194 int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num);
195 
196 bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr);
197 
198 int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key);
199 
200 #else /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
201 
202 static inline int
blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)203 blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
204 {
205 	pr_warn_once("crypto API fallback is disabled\n");
206 	return -ENOPKG;
207 }
208 
blk_crypto_fallback_bio_prep(struct bio ** bio_ptr)209 static inline bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
210 {
211 	pr_warn_once("crypto API fallback disabled; failing request.\n");
212 	(*bio_ptr)->bi_status = BLK_STS_NOTSUPP;
213 	return false;
214 }
215 
216 static inline int
blk_crypto_fallback_evict_key(const struct blk_crypto_key * key)217 blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
218 {
219 	return 0;
220 }
221 
222 #endif /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
223 
224 #endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */
225